Fragrance samplers comprising a microencapsulated fragrance and at least one binder layer between two surfaces are well known in the industry. These samplers have become a common vehicle for advertising perfumes and other fragrances through inserts in magazines and the like. Microencapsulated fragrance is typically provided as a laminate on one side of multi-colored, printed paper.
In a market that places a premium on appearance, the samplers of the prior art are deficient in that the area of the advertisement page that bears the microencapsulated fragrance is not printed with ink to match the rest of the device. This is because solvent-containing microcapsules cannot be coated easily onto water-borne inks commonly used in the printing industry. Fragrance microcapsules are usually coated from water-borne slurries that would adversely affect the underlying print quality. When the microcapsules are delivered from an organic solvent slurry, the selection of capsule fill and ink on the paper is limited. For environmental reasons, it is undesirable to deliver the microcapsules from an organic solvent due to the amount of volatile organic components that would be necessarily released. Although organic solvent-borne inks may be substituted for the water-borne inks, problems will occur when the fragrance is actually sampled by the consumer. Specifically, when the consumer applies finger pressure to collect the microcapsules, some of the microcapsules will rupture and release the fragrance oil (the organic liquid fill that is in the capsule, hereinafter, organic liquid capsule fill), which in turn will attack the underlying ink. The ink will then smear on the paper or actually transfer ink to the finger of the consumer. Problems with ink smear may also occur in fragrance samplers having microcapsules that are tightly bound to the paper, so called pull-apart or burst fragrance samplers, because the oils released upon fracture of the microcapsules may attack the ink and cause bleeding even though not physically wiped. Inks may also be adversely affected if there is capsule leakage even without separate wiping. The blank area on the page required to avoid having ink directly under the microcapsules renders a significant portion of the piece unavailable for advertising copy, and also often results in a harsh visual contrast to the overall appearance and graphic design of the advertisement.
U.S. Pat. No. 4,925,517 discloses the use of a base coating on a surface to be subsequently coated with a microcapsule-bearing layer. The base coating functions in part to control the rate and degree of penetration of liquid from the carrier for microcapsules into the underlying paper. Typically the base coating is softened by the carrier liquid of the capsule containing slurry as a means of controlling the bond strength within the sampling device. Preferred polymers to be used in the base coating are water-softenable or organic solvent soluble, as disclosed at column 5, lines 7-15.
U.S. Pat. No. 4,988,557 discloses a similar carrier activated base coating that is applied in a discontinuous pattern to provide separate areas of the sampler in which the capsules are ruptured when the piece is opened, as well as regions in which the microcapsules may be freely removed.
U.S. Pat. No. 4,876,136 to Chang, et. al. discloses a lipstick sampling device that is a three layered structure to deliver a small amount of lipstick to a potential customer. The construction comprises a carrier sheet, a window sheet and a cover sheet. The carrier sheet may be any film or sheet material, and is preferably paper that has an oleophobic impregnate or a barrier layer coated on one side. See column 3, lines 31-37 and column 5, lines 10-32.
U.S. Pat. No. 4,878,775 to Norbury, et. al. discloses a dry liquid applicator that is a support surface with a coating of relatively large microcapsules and with an overlay of a liquid permeable top protective layer. The bottom of the support surface is preferably not readily penetrated by the liquid in the capsules, and is preferably completely impermeable to the liquid. See column 2, lines 27-33. Samples of this construction were offered for sale that had ink printing on the bottom side of the structure, which was only viewable from the underside of the applicator.